The CNC system is a unit that issues a position command that requires an instruction to be transmitted accurately and quickly. After processing, a position command is issued for each axis. The servo system must follow the instruction to quickly drive the tool or table to move accurately. It requires the ability to quickly process blocks, control the processing error to * small, and so on. In the field of high-speed machining applications, the Siemens 840D and Fanuc18iMB * are representative.